The reasons remain unclear why one person will become addicted to a substance such as alcohol or heroin and why another will not. Some medical professionals argue that certain people possess traits that make them prone to developing an addiction. Others argue that a person cannot be described as having addictive personality disorder until he develops an addiction to something. Still others argue that an addictive personality disorder does not actually exist.
A person is addicted to something when she begins to use it not because she wants to, but because she feels she needs to. Addiction can be physical and psychological. When someone with a physical addiction stops using a drug, stops smoking, or stops drinking, she may go through withdrawal, as her body has come to expect the chemicals in the drug and cannot function normally without it. During a physical addiction, a person will need larger and larger amounts of the substance in order to feel any effects.
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Psychological addiction involves an emotional need and desire for a substance or an emotional need to perform a habit, such as shopping or gambling. Usually, a person will do whatever he can to get the drugs or perform the behavior when addicted. He may lie or steal to get the drugs or be able to gamble or shop if needed.
People who believe that addictive personality disorder exists argue that the addict's inability to control his behavior and an inability to delay gratification are common traits of the disorder. A person with addictive personality disorder does not know when to stop using something, whether it is drugs, sex, or gambling, leading to an addiction and dependence on that object. Depression, an inability to cope with stress, and a desire to fit in may also point to an addictive personality disorder.
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Antisocial behavior is another trait believed to be connected to an addictive personality. An addict may use a substance or engage in a behavior to show that she is different from everyone else or as an act of rebellion. The addict may feel isolated from those in her peer group and may use a substance or a behavior as a way to cope with the isolation.
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Some argue that addiction cannot be predicted, regardless of the traits a person may exhibit. The same people believe that an addictive personality disorder develops only once a person becomes addicted to a substance or habit. The traits associated with addiction develop after the addiction, much as some other disorders or diseases can change someone's personality.